用python实现排序算法
时间: 2023-09-25 19:10:34 浏览: 50
以下是Python实现的几种常见排序算法:
1. 冒泡排序
```python
def bubble_sort(arr):
n = len(arr)
for i in range(n):
for j in range(n-i-1):
if arr[j] > arr[j+1]:
arr[j], arr[j+1] = arr[j+1], arr[j]
return arr
```
2. 选择排序
```python
def selection_sort(arr):
n = len(arr)
for i in range(n-1):
min_index = i
for j in range(i+1, n):
if arr[j] < arr[min_index]:
min_index = j
arr[i], arr[min_index] = arr[min_index], arr[i]
return arr
```
3. 插入排序
```python
def insertion_sort(arr):
n = len(arr)
for i in range(1, n):
j = i
while j > 0 and arr[j] < arr[j-1]:
arr[j], arr[j-1] = arr[j-1], arr[j]
j -= 1
return arr
```
4. 快速排序
```python
def quick_sort(arr):
if len(arr) <= 1:
return arr
pivot = arr[len(arr)//2]
left = [x for x in arr if x < pivot]
middle = [x for x in arr if x == pivot]
right = [x for x in arr if x > pivot]
return quick_sort(left) + middle + quick_sort(right)
```
5. 归并排序
```python
def merge_sort(arr):
if len(arr) <= 1:
return arr
mid = len(arr) // 2
left = merge_sort(arr[:mid])
right = merge_sort(arr[mid:])
return merge(left, right)
def merge(left, right):
result = []
i = j = 0
while i < len(left) and j < len(right):
if left[i] <= right[j]:
result.append(left[i])
i += 1
else:
result.append(right[j])
j += 1
result += left[i:]
result += right[j:]
return result
```
以上是常见的几种排序算法的Python实现。